Acceptable combinations determined by reference to known words, not application of abstract rules (massgeneral.org)
The utilitarian can confidently say, «Better to save one life than none at all»; no abstract rules about justice or fairness should count more than increasing the utility in the world. (religion-online.org)
The starlings could do this even when the researchers stuck two or three extra «warbles» or «rattles» into the middle of the song, indicating that the birds had come up with an abstract rule that guided their pecking behavior, says Gentner. (sciencemag.org)